(CNN) - (CNN) – Nancy Reagan, wife of former President Ronald Reagan, wrote in a statement Thursday she had endorsed GOP presidential contender Mitt Romney.

"Mitt and Ann Romney joined me at my home this afternoon for some lemonade and cookies and I offered my firm endorsement of his campaign for President," Reagan wrote. Romney was in California Thursday to attend campaign fund-raising events. He also made a stop at the headquarters of Solyndra, the failed solar energy company.

Nancy Reagan said in her statement her late husband would have liked Romney's background.

"Ronnie would have liked Governor Romney's business background and his strong principles, and I have to say I do too," she wrote. "I believe Mitt Romney has the experience and leadership skills that our country so desperately needs, and I look forward to seeing him elected president in November."

On Tuesday, Romney passed the "magic number" of delegates required to secure the GOP presidential nomination. He will not officially be the Republican nominee until this summer's Republican National Convention in Tampa.

Last week a spokesman for Nancy Reagan said the former first lady was recovering from a number of broken ribs after a fall sustained in March.

Mrs. Reagan, 90, was unable to attend a speech given Tuesday evening by House Budget Committee Chairman Paul Ryan, R-Wisconsin, at the Reagan Presidential Library in Simi Valley, California.

Since President Ronald Reagan died in 2004 from Alzheimer's disease, the former first lady has been involved with the National Alzheimer's Association and its affiliate, the Ronald and Nancy Reagan Research Institute in Chicago.

However, she has been hospitalized at least twice in recent years and her public appearances have been rare.